Academic literature on the topic 'Dermestes maculatus'

Piper guineense fruits were purchased, sun-dried (30±2oC) for 10 days and ground into fine powder. Fifteen (15) pieces of Clarias gariepinus (300 ± 5.0 g) were procured and smoke-dried in the laboratory using a charcoal-powered smoking kiln at 65oC for 10 hours. Each smoke-dried fish sample was placed in a plastic container with perforated lids covered with muslin cloth and Piper guineense fruit meal was sprinkled at varying quantities (0.0 g, 2.5 g, 5.0 g, 7.5 g and 10.0 g). Ten (10) adults of Dermestes maculatus bred from highly infested smoke-dried fish samples were introduced into each container and covered air-tight for seven (7) days. Mortality of D. maculatus was significantly different (p = .05) in all treatments and increased with an increase in the quantity of P. guineense and number of days. Mortality ranged between 73.33 and 100 % in treated groups while none was recorded in the control. Chemical compositions in treatments showed an increase in crude protein, lipids and lower moisture content at higher inclusion levels. This study showed that P. guineense can prolong the shelf-life of smoke-dried C. gariepinus against D. maculatus while retaining its nutritional composition.
 Key words: Dermestes maculatus, Piper guineense, smoke-dried, Clarias gariepinus

The larvae of the Beetle Dermestes maculatus De Geer can subsist on a diet consisting largely of protein. Studies have been undertaken to investigate the nature of proteolytic enzymes. A water extract of the larvae yielded a crude preparation that hydrolyzes gelatin, bide powder, hemoglobin substrate, benzoyl-DL-arginine p-nitroamilide, and glutaryl-L-phenylalanine p-nitroanilide. Enzyme activity was found in a non-dialyzable, heat- and acid0labile portion of the extract yielded two fractions with high specific activity towards gelatin. These are precipitated between 40% to 60% saturation of ammonium sulfate and 60% to 80% saturation. The higher specific activity was observed in the 40%-60% fraction. These results suggest that the larvae of these dermestids contain proteolytic enzymes with actions similar to mammalian trypsin and chymotrypsin. The results also suggest that other proteolytic enzymes may be present as well.

Introduction: Numerous studies have examined the effect of abiotic factors on the development and survival of Dermestes and their importance for forensic entomology. Dermestes maculatus is one of the most known beetle species associated with corpses and D. caninus has little biological information available and no case report records. To better understand the life-history traits of those species we evaluated the impact of diet type and intraspecific larval density. Methods: Adult beetles were collected from human remains and colonies were kept under controlled conditions (27.0 ± 1.0 °C, 55.0% RU, and 12:12 L:D) and F1 generation was used to collect eggs. Newly emerged larvae were separated according to the treatments, being the combination of larval density (1, 15, 30 individuals), food (dried dog food or dried pork) and contact (with or without). We used factorial-ANOVA to test the individual and combined effect of both larval densities and diet on dependent variables, followed by post-hoc Tukey test. Pearson correlations were carried out to evaluate the relationship between larval parameters for each species in each treatment. Results: Pork-based diet positively affected species fitness, with larvae being ca. 1.1 (D. caninus) and 1.7 (D. maculatus) times bigger and heavier than in dog food. Diet type also impacted the development time for both species. Conclusions: Data generated through the current study serve as a foundation for potential application of this species as an indicator of time of colonization in relations to a minPMI. However, validation is still needed to determine the accuracy and precision of these calculations.

Neem, Azadirachta indica, products were tested for toxic, growth regulating, primary antifeedant, and secondary antifeedant effects on Dermestes maculatus, under conditions approximating those found in storage facilities. Toxic and growth regulating effects were investigated using topical application of mineral oil, neem oil, purified azadirachtin/methanol solution, and 10% neem seed kernel extract/methanol solution. All neem treatments exhibited higher mortality than the mineral oil treatment 5, 10, and 14 days after the application of the treatments; larvae treated with neem products often failed to pupate and never emerged as adults. Primary antifeedant effects of azadirachtin (1.5 g/L and 5 g/L) were investigated with an original no-choice feeding bioassay. Significant primary antifeedant effects were observed which were persistent for up to 13 weeks for adults and 17 weeks for larvae. Significant secondary antifeedant effects were also demonstrated after topical application of azadirachtin (.125 g/L, .25 g/L and .5 g/L) to the larvae.

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, 2012<br>Various insect taxa are known to modify bone with their mandibles, including members of the orders of Dermestidae, Tenebrionidae, Calliphoridae, Tineidae and Termitidae. Despite bone modification being a known behavioural trait of many of these taxa, little work has been done to record the distinctive ways in which they modify the bone surface, and a lack of concise descriptions of modification suites inhibits decisive identification and interpretation. The most widely inferred causal agents in palaeontological literature are either termites or dermestid beetles, whilst cockroaches as potential bone modifying agents have not yet been considered. The primary aims of this investigation were to establish whether or not cockroaches and dermestids modify bone, and if so in what ways, develop an interpretative framework to aid future researchers in the identification and differentiation between the variously reported agents of bone modifications, test whether or not the agents will modify bone of varying densities (thin cortical, thick cortical, compact and cancellous bone) or in a particular state of preservation/condition (fresh, dry, weathered or fossilised), and investigate whether or not the occurrence of insect modifications on bone can be used as a proxy to establish a broad climatic signature based on their known thermal physiological limits. A single experimental trial of 18 bone specimens were exposed to the African cockroach Periplaneta americana for a period of six months and a further four experimental trials (totalling 80 bone specimens) were exposed to the Coleopteran Dermestes maculatus for periods of four months each under the absence or presence of substrate and variable feeding conditions. Experiments were conducted within an insectary at 28° C, 40 % humidity and 12 hour light/ 12 of darkness. Subsequently, all specimens were viewed using an Olympus SZX 16 Multifocus microscope fitted with a digital camera at magnifications between 7 and 115x. Three modification types were identified for P. Americana, namely discolouration, destruction of bone and gnawing. A total of five modification types were established for D. maculatus including the occurrence of surface tunnels, destruction of bone, bore holes, surface pits (Classes 1–3) and gnawing. Three distinctive surface pits morphologies were identified; Class 1 pits are highly variable but most often semi-circular to elliptical shallow depressions with a U-shape profile with striations radiating around the outer circumference of the depression. Class 2 surface pits are semi-circular shallow depressions with randomly orientated striations occurring over the entire feature. Class 3 surface pits are irregular shaped depressions with complex profiles not associated to gnawing striations. Broad climatic signatures for both of these agents were developed based on their known physiological thermal limits. The indistinct modification signature of P. americana in combination with limited occurrence and frequency patterns may prove difficult to identify from an archaeological or palaeontological context. Periplaneta americana and D. maculatus do significant damage to aves bones, which could result in their under representation in the archaeological and palaeontological records. The highly distinctive signature as well as occurrence and frequency patterns of modifications produced by D. maculatus has enabled the reinterpretation of existing palaeontological analyses, suggesting that dermestids are in fact not responsible for reported instances in which they are suggested as the causal agent during the Mesozoic and Cenozoic.